In order to overcome the limitations of currently available assistive technologies for minimally invasive cardiac surgery (MICS), we propose to develop and test an innovative approach based on a highly articulated robotic probe (HARP). We believe that, for procedures involving epicardial interventions on the beating heart, MICS can be effectively realized with the HARP, entering the pericardial cavity through a subxiphoid port, reaching remote intrapericardial locations on the epicardium without causing hemodynamic and electrophysiologic interference and delivering therapeutic interventions under the direct control of the surgeon. The main goal of the HARP is to extend the sensing and manipulation ability of the physician by taking advantage of the high maneuverability of the HARP to steer around organs and reach anatomical landmarks which are not accessible to the conventional rigid and flexible endoscopic tools. We chose minimally cardiac surgery as a focus domain or, more specifically, subxiphoid videopericardioscopy as our target application because it represents all of the challenges that most procedures would have and has significant merit on its own. As an exemplary application that, in our opinion, sums most of the challenges that can be encountered with a broad array of epicardial interventions on the beating heart, we hereby propose to test the use of the HARP for the ligation of the left atrial appendage (LAA), a clinically relevant approach to reduce the risk of stroke in atrial fibrillation. We strongly believe that addressing this exemplary application represents a challenge that will enhance HARP's functionality and will eventually lead to expansion of its application to multiple intrapericardial therapies (e.g. cell transplantation by intramyocardial injection, epicardial ablation, epicardial lead placement for resynchronization, etc). With respect to this clinically relevant application, we hypothesize that the HARP will achieve superior results when compared with the existing rigid subxiphoid videopericardioscopy technology for intrapericardial navigation, which in turn will allow for ligation of LAA.The specific aims are designed to further develop the existing 12mm HARP prototype, and then to test it and comparing it to the existing subxiphoid videopericardioscopy device in an anthropomorphic phantom, in animals and human cadavers. Our broad, long-term objective is to fulfill our group's "epicardial frontier" vision, enabling a growing portfolio of epicardial therapies by developing and testing new dedicated innovative robotic technology. We envision the adoption of HARP-based intrapericardial therapies not only by minimally invasive cardiac surgeons, but also by interventional cardiologists and electrophysiologists. We also believe that the HARP may expand the therapeutic options for other non-cardiac endoscopic applications .